General guide

When the electrical system is operating normally the battery will not be charging nor discharging! This is because the battery is fully charged and the bike is 'running' off the alternator. To get to this state the battery must be recharged to make up for the large discharge of the stater motor, this may take 15 minutes. So brief measurements of the battery current won't tell you much.

The voltage readings tell a lot more .. anything less than 13 volts is bad when the bike is running. Less than 12 is untenable and you need to instantly reduce the electrical load.

The battery should sit at 13 volts or more for say 15 minutes before you shut the bike down - this ensures you have some charge in the battery to start the bike next time.

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Barry
Did the bike carry this electrical load at some previous time? Or have you just made the changes and found this problem? :confused1:

This tells us that

1) the bike can do it
OR
2) the bike may not do it .. simply too much load.

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You certainly cannot increase your present electrical load (under present conditions)! You would be well advised to actually reduce it! To start with the dual high beam - make it single, or keep to low beam.

For wiring faults; Check the wires and connectors ... for heat - use your hands to feel for it .. where it is warm you have a problem ... do this with your high electrical load on. The places you want to check are from the alternator to the battery - around the rectifier/regulator is a good place to start. Try not to burn yourself

Good luck.

Youre using way too much current with the dual highbeam, simple as that.

Yeah, I thought that the dual hi beams may be the problem. Still tryin to chase down an ammeter to confirm my suspicions that I'm trying to draw too much. Ive tried a different regulator and the problem still exists, but I'm not convinced the new regulator is any good (language barriers can be a real bitch when trying to do something very specific).

Warin - I bought the bike wired with dual hi beams so you would think it'd handle it. But then again, one of the previous owners has also wired a jump point on the outside of the bike, so it probably has had electrical issues b the past.

The reson I thought it important to check the current draw from the batter is that I believe the bike should never be using the batter while the engine is running, regardless of the state of charge of the battery. Any such condition indicates that the charging system is not providing enough power to run all the electrics.

When the engine is at low speed (idle) the battery will be providing some power, more if you have stop light on, more if you have indicators on, and much more if you have the headlights on. At idle the alternator is at minimum power and may only just provide power for your ignition system.

As the engine speed increases the alternator power increases too, but it is not a linear relationship. See the Car and Deep Cycle Battery FAQ, Battery Manufacturers and Brand Names List, and for info (section 5).

From your given info I suspect the dual hi beam was added by an over enthusiastic owner .. who only used it for short periods of time .. or who realized he had a problem and sold it off.

Remove the dual high beam

At idle the bike should charge fine with a normal 60/65w headlight, and 5w rear, and all the instruments working......Mine does, i've got a voltmeter fitted to the bike.

Again....Turn of one of the front lights, and you should be good to go.

You can always save a few watts if you get a BAY15D SMD bulb for your rear stop/brake lights!

It WAS the law. That law has been repealed as the statistical results said it made no difference. So you can now turn your headlight off in Australia. But some motorcycle manufactures are not equipping their bikes with the switch... makes it common with some other markets who also don't have a headlight switch. But you can legal turn the headlight off, you just need a way of doing it.

Faulty wiring! I realised that I had checked that there was no voltage drop between the regulator and battery, but with no load and a bad battery! Checking again under full load and with a new battery, I found almost 1 volt drop from the regulator to the battery. So I cleaned all the contacts, added solder to the joints, thickened the wire and shortened the amount of wire between the regulator and battery (all on +ve side). Now it'll maintain 14.4V with normal lights, and 12.9V with the dual hi beam, which is not ideal but at least should not drain the battery. To save power I got some of those delivery scooter hand covers so hopefully I won't need the heated handgrips as much (although I am loath to make my tenere wear them, I think it's better to look like a pizza delivery bike than always ask for a jump)

Thanks for the help, I'll post here again after testing the viability of the dual hi beams on a bit of a ride.

12.9 won't damage the battery in the short term. But you'll want to run it higher 10 to 15 minutes before your stop to have enough energy to start the bike the next morning. As you'll probably want to run at a slower speed with the light reduction that will cool the motor too, a good thing to do.

Some led's for the instrumentlight, and the rearlight should save up some extra wattage to get the voltage over 13v.

I'd still use an on/off switch so you could turn of one of the frontbeams, when its not really needed. Or perhaps change one of them for a "smaller" one in the 30-50w area, it should really help

The saving is very small when compared to the overall power.

The instrument lights are 3 watts each, the tail light is 5 watts .. so if LEDs save half and you have two instrument lights you'd save some 7.5 watts out of some 168 watts ... less than 5% saving.